Infinite loop Affecting nanoid package, versions <3.3.16>=4.0.0 <5.1.16
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-JS-NANOID-18506894
- published2 Aug 2026
- disclosed29 Jul 2026
- creditsajdakabir
Introduced: 29 Jul 2026
NewCVE-2026-67214 (opens in a new tab)How to fix?
Upgrade nanoid to version 3.3.16, 5.1.16 or higher.
Overview
Affected versions of this package are vulnerable to Infinite loop through the customAlphabet and nanoid functions in nanoid/non-secure. An attacker can hang the calling thread by supplying a negative size to either function, causing the loop counter to decrement from a negative value and never reach its termination condition. This affects applications that pass unvalidated attacker-controlled size values into the non-secure ID generator, where a single malicious request can spin the process indefinitely and stop the service from responding.
Notes
- The vulnerable code path is in the
nanoid/non-secureentry point, so bundles or consumers that import the non-secure module directly are the ones exposed; the secure/default package path is a separate export. - The denial-of-service only shows up when callers pass a negative
sizeinto these APIs, which the advisory’s regression tests treat as returning an empty string rather than looping.